Well surveying instrument



' Mme-5s.-

/Mq V G. L. KoTHNY wsu. sunvanne Insmmmur Filed July 2a, 194:',

2 Sheets-Sheet 2 Passed Fenna 1941 annals sentarme nis'rnmmm' Application .duly 28, 119413, Serial No. 496,441.

'I'his invention relates to a well surveying instrument and has Particular reference to the surveying oi! bore holes by the so-called go-devilA method.

In the patent to Roland Ring 2,246,319, dated June 17, 1941, and in an application of said Roland Ring, Serial Number 379,835, filed February 20, 1941, there are described an instrument and methods of operating the same, which instrument is characterized by a slow and continuous recording action, specifically electrolytic in character, whereby a record of the position of the instrument within a bore hole is made only when the instrument remains stationary for an extended period `of time. Fora better understanding of the nature oi' the present invention, which is not, however, limited for its application to said instrument of the above-mentioned patent and application, the operation oi said Ring instrument may be described as follows:

If the instrument is run into a bore hole either withina drill stem or in an open hole by means of a wire line or a cable, the movements of the in- 'I strument incidental to its descent into the hole cause a pendulum to move about relative to a record member so that even though current is continuously iiowing from the pendulum to the record member, no point of the record member is exposed to the current action for a sufllciently long time to receive a definite marking. When the instrument reaches the level at which a rec-l ord of inclination is to be made, it is brought to rest and held in such position for a period of up wards -of about one minute with the result that the electrolytic action is concentrated at one point of lthe record member and an easily distinguishable spot is Amade thereon. If it is then desired to make one or more additional records at other levels, the instrument is moved to these successive levels and permitted to remain at them for definite periods of time with the result that marks diiiering in intensity and/or siae are produced which, by their nature, can be identiiied with the particular levels througha knowledge of the relative times during which the instrument was stationary. Following the completion of the record or records, the instrument is then withdrawn continuously from the hole, and in this withdrawing movement, as well as in the periods of movement between the successive recordings, the pendulum will swing relative to the record member so that again no obliterating markings are produced.

In the case of operationo! the above type, the instrument is perfectly satisfactory and requires no timing means whatever. However, a common.

. il@ Gils. (ma-055) practice in the making of records with other types of surveying instruments involves their being dropped freely through a drill stem so that they come to rest in a position adjacent the bit. Dur ing this location in a position of rest, a record is made under the control of'suitable timing means, and the instrument is then recovered when the bit is brought to the surface, for example, for the purpose of changing the bit or checking its condition.

In the use of said Ring instrument in go-devil fashion, the motion of the instrument through the drill stem prevents the making of any records during its fall, and a record is then made by holding the drill stem stationary for a sunicient period of time while the instrument rests adjacent the bit. If the drill stem was then raised and disman-` tled by continuous work ofthe drilling crew, the instrument would be subject to suiciently continu uous agitation with only quite limited periods of rest so that no record-obliterating markings would be produced on the record member. However, it is not usual for a derrick crew to work continuously in removing a drill stem from deep v holes and, generally speaking, even if some mechanical reason for delay does not occur, the workmen after raising the drill stem part way, will take a short period of rest before proceeding further. If an instrument of the Ring type is in. the drill stem during such a period of rest or any other period of stationary condition of the drill stem, it will be obvious that another record will be made which might be indistinguishable froml the desired record unless a substantially deflnite time of rest is involved; and even then in some rare instances, particularly where the hole is substantially vertical, the two records may overlap so that the significance of the original one is lost. It is generally undesirable to rotate the drill stem 4o during such a period of interruption of its withdrawal and consequently such rotation is not a practical solution .to the problem. u'

The present invention relates to the provision oi' means for terminating therecording action of a recording instrument of the Ring or other type at a desired time. Specifically, in accordance with the invention this is eiected by controlling the current flow in accordance with the mud pressure encountered by the instrument in its location in the hole.

u Figures 1A, 1B, and 1C represent longitudinal sectional views through lower. intermediate, and

assunse A in is basically of the type disclosed in said Ring appiication and comprises a protective casing capable of withstanding mud pressure which includes sections 2, d, t, and 8 and the closure i0 embodying a Spearhead. An inner casing comprises the sections i2 and i6 joined by a coupling it.. The upper end of the section i8 is closed by the ping it, while the lower end of the section i2 is closed by the plug 20 to which may be secured the record member 22 by means of a threaded ring 24, though the record member may be otherwise secured in the plug. for example by being depressed within a flanged portion thereof. This record member, as described in ydetail in said Ring patent and application, preferably comprises a sheet of paper containing a colored materiai such as a colored metallic errocyanide which, upon the passage of an electric current while it is moist, will be marked with a white or contrasting spot by reason of the formation of v ailraii at a cathode provided by a metallic point 2t slidabie within a pendulum 26 mounted for universal pivotal movement in a bearing arrangement in insulating ring 32 prevents a short circuit by preventing contact of the pendulum,-

with the metallic wali of the tube i2.

'The bearing 3d is carried by the lower end of` a cyiindricai pin 3i which extends through an opening in the coupling member il and is insulated therefrom as indicated in the drawing. Within the pinl there is located a resistor t6, the lowerleadof which is soldered within an opening in the pin, while its upper lead is electrically connected to an insulated contact button ii on which may rest the bottom of the lowermost oi' a group of batteries H0 arranged in series in ashlight fashion and held within an insuiating tube 42. Contact with the positive pole of the uppermost battery is made by means of a metallic pin il urged downwardly by a `vwith an insulated contact button 53 connected by means of a wire 54 to a metallic contact disk 56, the wire 54 being desirably in part helical to permit expansion and contraction,` this portion being located within an insulated sleeve 5S to avoid contact with other metallic parts of the apparatus. The contact button 56 is mounted within an insulating assembly 68 and provides a seat for a spring 51 which urges upwardly a pin 54.

A spring 58 is secured at its lower end to the member 52 and at its upper end to the insulation assembly 86 thereby providing a resilient support for the member 52 so that the interior instrumene is supported mmc snoek between the spring and a lower cushion spring B9. It will he evident that the element described provides a conductive connection between the positive pole of the uppermost battery and the pin Il, the connections being insulated from the casing.

Tl'irough a stumm; box I8 and other packing et there extends a. pin 10 connected at its upper end to a piston i2 provided with an axially extending opening 78. A strong spring i8 normally urges this piston to its uppermost position, the spring being initially very substantially loaded as described hereafter.

Threaded into the bottom il of the chamber @C in the casing section lisa post provided with .a bore communicating through one or more lateral openings with the interior o! the cap-like member 82 forming a. sand trap. An arrangeposition and, therefore, with the plunger 1li out of contact with the pin 6l, the circuit of the batteries 40 is open so that no recording will occur. As the instrument passes downwardly through the mud in the bore hole, inside the drill stem, if it is being used in go-devil fashion,l

or supported by a wire line if lowered in that way, the circuit will remain open, no dependence being had in the operationoi this modification.

upon the motion of the pendulum to prevent the making of a record during the initial part ci the lowering operation.

Eventually the effective pressure on the assembly of the piston 12 and its plunger 'Ill will overcome the preloading of the spring li and will. start the piston i2 moving downwardly ultimately to bring into contact the plunger 'Il and the pin El. When this condition is attained, the electrical circuit is closed, the positive pole or the uppermost battery being now grounded, and, consequently', the instrument is ready to make a record. Recording is prevented, however, by the continued movement of tl'e pendulum until the instrument reaches vits final position of rest, for example, adjacent the bit of the drill stem. It is now permitted to remain in such position for a sumcient period oi' time to make a record of inclination. if desired, the drill Astem may then be lifted to bring the instrument to another level. or the wire line may be withdrawn if the instrument is attached thereto. to make a second record, the instrument remaining at rest for a period of time different from that during which the instrument was at rest for the making of the tlrst record. This operetion may be again repeated provided that the instrument remains at a suillcient depth so that the pressure oi' the mud maintains contact between the plunger 10 and pin Il.

In order to interrupt the record, it is then only necessary to lift the instrument to such height that the mud pressure existing there is insumcient to keep the' piston and plunger assembly in a suiiiciently lowered position to produce electrical contact with the pin Il. As soon as the instrument is above such level, recording ceases and if it has been kept in motion between recordings theretofore. it may remain at rest' 'for Vof the record. It will be evident that the spring 16 used should be so chosen as to conform with the depth at which recording is to occur and the density of the mud in the hole. For example, with a single recording instrument there may be provided a number of springs or, more conveniently, a num@ ber'oi complete sets of the assembly comprising the sections 44, 6, and 8 of the protective casing and their contents, or various parts thereof. In this fashion, there may be provided springs i6 of different strengths and diilerent degrees of preloading so that by suitable choice of a spring, the operator may insure that the piston '|2 will begin to move downwardly only after a certain depth is reached and additionally insure that at the desired depth of recording the electrical circuit will be complete so that the recording may take place. Thereupon 'after withdrawing the instrument to a predetermined depth, the circuit will be interrupted to stop the recording operation. Instead of using various springs, a single spring 'I8 may be used subject to predetermined adjustment of its preloaded condition, for example, by supplying various lengths of tubes 6 with corresponding rods 10.

'Figures 2 and 3 illustrate a modified form of device also pressurecontrolled but involving a somewhat diilerent 'mode of control. In this modiilcation the protective casing involves the sections 00, 02, and 9.4, the last being capped by the spearhead 0B. The surveying instrument within the protective casing is indicated at 98 and except for the detail of its top plug, this instrument is identically that described above to the extent. that Figure 1A may be considered as showing the portion of the instrument below Figure 2, the uppermost of the batteries in this latter modification being indicated at |00. 'I'he topplug |02 of the instrument 98 contains a pin |04 pressed downwardly to engage the positive pole of the uppermost battery by a spring |06 which, in turn, bears upon a disk |08 engaging the head of-a spindle ||0 which carries an arml ||2lhaving an upturned portion as illustrated.

-The various elements just mentioned are mounted in insulating inserts in the plug |02 so that there is no grounding through any of these'elements of the positive pole of the uppermost battery.

The upturnedend of the arm ||2 projects between the arms v||4 and ||6 of a member carried by an lupright shaft |20. The arm ||4 is adapted to be engaged by the arm ||2 to provide a metallic electrical contact but the arm Iltis provided with an insulating pad H8 so that electrical 'contact between the arm ||6 and the end of the lever |2 is prevented.

The shaft |20 has its axis extending along the axis oi'. the instrument andcarries a disk |22 v to whichthere is secured the closed lower end 6 lever clockwise as viewed in Figure 3 to engage the arm ||2. 1

The upper end of the helical tube |24 is se- I cured to the portion |26 of the casing section 94. Its interior communicates through a passage |28 and the sand trap |39 with the chamber |32 which, in turn, communicates with the exterior of the instrumentthrough passage |34.

In the use of this apparatus, the parts illustrated in Figure 2 are assembled with the parts;

illustrated in Figure 1A, a moistened record disk being in place beneath the pendulum. As the instrument drops through the drill stem, the pressure of the mud will cause a rotation of the shaft to cause the arm H4 to engage the arm 2 with a resulting grounding of the positive pole of the battery |00 thereby completing the electrical circuit. Under these circumstances,

' however, recording is prevented by reason of the motion of the pendulum during the descent of the instrument. 'I'he spring |06 through the disk |08 imposes a quite substantial friction on the spindle ||0 and, consequently, while the arm H2 will be rotated by engagement by the arm H4, there will be maintained uniform continuous contact. This is not important duringthe descending operation, but it is important to insure that when the instrument reaches the bottom there is electrical contact between ||2 and H4. When the instrument reaches the bottom'of the hole and comes to rest, the circuit will then remain completed and after the pendulum comes to rest, a record will be made by holding the instrument in iixed position for a predetermined length of time.

If the instrument is now withdrawnby removal of the drill stem, it must rise only through a relatively small distance before the relief of pressure in the tube |24 will cause the shaft |20 to rotate in a counter-clockwise direction as viewed in Figure 3, breaking contact between H2 and 4. As a result, even if removal of the drill stem is interrupted so that the pendulum may become stationary, the circuit is broken so that no further recording will take place. As the instrument is further withdrawn from the hole, the pressure will continue to decrease with the result that the insulating pad ||8 will engage the arm I2 rotating the same backy to its original position when the surface is reached. During all of this reverse rotation, however, it will be obvious that there will not be remade the circuit through the pendulum so that there can be no further recordingdespite cessation of movement.

As contrasted with the first modification which is adapted to operate at a definite depth range depending upon the nature oi' spring |6, the modification of Figures 2 and 3 is adapted for universal application at any depths within a very wide range. For example, the electrical circuit is made as soon as the instrument is lowered to a depth which will cause the arm to move through an angle equal to the angle of clearance of the arm 2 between 4 and ||8. From then on as the instrument is lowered,l the electrical contact is maintained. As soon as the movement is reversed, i. e.,- the instrument is raised,

. the contact will be broken and during the raising operation, the contact will be maintained broken. It will thus -be seen that all that is necessary to secure a record is to insure that immediately prior to the making of the record, the instrument is lowered through such distance that the increase in hydraulic head would insure contact. For example, if a plurality of records are to be made.

ateniese' I the instrument may be nrst lowered to the rlrst recording level. 'Then it may be raised above the next recording level a distance equal to the hydraulic head corresponding to the clearance referred to above and then lowered to this latter level with the assurance that. contact will be re made tor the second record. This procedure may then be repeated as oftenv as desired, the records being distinguished from each other Toy mainatenance oi' the instrument in stationary condi-4 ".tion i'or deilnite periods of time.

,f-Sff 'Instead of using a Bourdon tube i for securing rotation of the contact elements, it wiilbe evident that a'piston may be used provided with a helical groove through which rotation may be imparted to an arm such as ill.

What is claimed is:

l. A well surveying instrument comprising means for supporting a record member, slowly acting means lor recording inclination of the instrument on said record member', and fluid pressure responsive means for interrupting the recording action. l

2. A well surveying instrument comprising means tor supporting a record member, means for recording inclination o! the instrument on said record member, and means responsive to liquid pressure about the instrument for interrupting the recording action.

s. A well surveying instrument comprising means forsupporting a record member, means i'or recording inclination of the instrument on 8 for recording inclination of the instrument on said record member. and duid pressure responsive means ior controlling the recording action, said pressure responsive means comprising g member movable under external pressure against a pre- Aloaded spring to eilect the control in a predetermined depth range.

9. A well surveying instrument comprising means for supporting a record member, means for recording inclination of the instrument on y said record member, and duid pressure responsive means lor controlling the recording action, said pressure responsive means comprising a piston movable under external pressure against apreloaded spring to eil'ect the control ln a predef -termined depth range.

10.A well surveying instrument comprising means tor supporting a record member, slowly acting means for recording inclination of the insaid record member, and means responsive to.'

changes or liquid pressure about the instrument incidental to substantial vertical 4dlsplacemeiits thereof within a bore hole for interrupting the recording action.

i. A well surveying instrument comprising,

means for, supporting a record member, means for recording inclination of the instrument on said record member, and means responsive to changes oi' liquid pressure about the instrument incidental to substantial vertical displacements thereof within a bore hole for controlling the recording action.

5. A well surveying instrument comprising means for supporting a record member, electrically operating means for recording inclination of i the instrument on said record member, and means responsive toiluid pressure about the instrument i'or controlling the circuit of said electrically operating means.

6. A well surveying instrument comprising means for supporting a record member, eloctrically operating means for recording inclination of the instrument on said record meniber, and means responsive to iluid pressure about the instrument for controlling the circuit of said electrically operating means to interrupt the recording action.

7. A well surveying instrument comprising means for supporting a record member, means for recording inclination of the instrument on said record member, and'iluid pressure responsive means acting upon substantial rise oi said instrument within a bore hole following a lowering thereof to control the recording action.

8. A well surveying instrument comprising means for 'supporting a record member, means strument on said record member, and means responsive to liquid pressure about the instrument for interrupting the recording action.

ll. A well, surveying instrument comprising means for supporting a record member, slowly acting means for recording inclination of the lnstrument on said record member, and'means responsive to liquid pressure about the instrument ior controlling the recording action.

l2. A .well surveying instrument comprising means for supporting a record member, slowly acting means for recordinginclination of the instrument on said record member, and means responsive to changes oi' liquid pressure about the instrument incidental to substantial vertical displacements thereoi' within a bore hole for interrupting the recording action.

i3. A well surveying instrument comprising means for supporting a record member, slowly acting means for recording inclination oi' the instrument on said record member, and means responsive to changes of liquid pressure about the instrument incidental tosubstantial vertical 'displacements thereol within a bore hole for controlling the' recording action.

14. .A well surveying instrument comprising 'means for 'supporting a record member, slowly acting means for recording inclination of the instrument onl said record member, and fluid pressure responsive means for controlling the recording action.

- GO'I'IDANK L. KOTHNY.

nul-misses CITED The following references are of record in the 

